Child restraint systems for automobiles are frequently designed to employ conventional seat belt and shoulder harness for strapping the child onto a child's seat placed on a conventional passenger seat, or in the case of children who do not require an auxiliary child's seat the harness may be applied to the child as in the case of an adult. In either case, where the child's feet do not touch the floor of the vehicle, the belt and shoulder harness restraining system may be required to hold the auxiliary seat, or child without such seat, against moderate deceleration or turning of the vehicle to prevent, forward pitching or lateral auxiliary seat tipping.
Where inertia responsive retractors are employed to accommodate free forward leaning of the passenger in the absence of sudden deceleration, such systems may be ineffective to adequately restrain children, either in auxiliary seats or otherwise, where foot bracing by the child is unavailable. In order to meet this problem, various means have been employed to lock the retractor when the restraint system is applied to a child as by a manual, lever, push buttom or other device located on the retractor housing adjacent the reel latch. Such solution has not been entirely satisfactory, particularly where the retractor housing is at an inconvenient location.
Accordingly, vehicle manufacturers have recognized the need for some means to convert a vehicle sensitive inertia retractor to an automatic locking mode which would be convenient for the adult applying the restraint system to a child; for example, in response to fully extracting the webbing whereupon retraction by the wind up spring would ratchet the latch to an automatic locking condition when all webbing play has been taken up with the child, including any auxiliary seat, in required restraint position.